foo.cc: In function 'int main()':
foo.cc:39:3: warning: 'flag2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   39 |   if(flag2==1)
      |   ^~
foo.cc:30:4: warning: 'flag' may be used uninitialized in this function [-Wmaybe-uninitialized]
   30 |    if(flag==1)
      |    ^~

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